json services

I'm new to both services and json.
What I would need to achieve is to have a field on registering a new user to be checked if the value is present in another database using json. And if it is, go ahead registering the user otherwise throw an error message.

I don't want to store the data in Drupal. I need to read JSON data from external URL and render that in my theme.

I could use Feeds and JSONPath Parser module if I want to store in Drupal but I just want to read. I am also tying Services module.

Any suggestions, tips would be huge help!

Thanks in advance

UPDATED

I'm working on adding points to a map from a drupal json service. I have it pulling the data in but its only placing one location and not all of them. Each location should get placed but it isn't. I'm not sure what I am doing wrong. Can anyone help? Below is the code.

Thanks

var lat = '';
var lon = '';

var url = 'http://localhost:8888/testsite/services/json';

var data = [];

var view = new Object;
view.method = 'views.get';
//view.hash = hash;
//view.domain_name = domain;
//view.domain_time_stamp = timestamp;
//view.nonce = nonce;
view.view_name = 'yardsales';

I'm using Sumitk's great example on using Titanium with Drupal JSON service. I can pull in view data and display it correctly and link to the node in a webview. I'd like to just get a node. I've modified the views.get example to get the node but it isn't displaying.

I have a tableview with links to different durpal content like a view of nodeA. One title I want to link to a node. I it linking to 'page.js' which has the below code.

var url = 'http://localhost:8888/testsite/services/json';

var win = Titanium.UI.currentWindow;
win.backgroundColor = '#dce0e4';

var data = [];

This is intended to be an initial set of resources for those looking at getting started in this exciting area of drupal/mobile app development.

These resources are largely the work of Sumit Kataria of Civic Actions and my interest and excitement stem from this awesome presentation at Drupalcon SF2010 http://sf2010.drupal.org/conference/sessions/developing-apps-iphoneipada...

The presentation is broken down a little further with some provided code samples and an adjusted json server module.

I'm having trouble wrapping my head around services. I was hoping a post here might yield some fruit. I have an interest in creating a "Content API" for my site--so that other people could submit custom queries to my drupal db and have something like a JSON object returned to them with the resulting content in it.

I'm using JSON in Flash (because I'm also using JSON for iPhone and wanted to keep things consistent rather than mixing amf and JSON). I noticed that when I started using the JSON Server for the Services module that strings with apostrophes were getting slashes where they didn't belong. Check out the return differences between these:

I am trying a simple test with Drupal 6, Services, JSON Server but am running into the following error. To make things as simple as possible, I tried this with the curl command line program (although I have also tried it in python and php). I have services and json server installed and can go to services at mysite.com/admin/build/services/browse/service.name and successfully browse a view I made using views.get. I also did this with node.get However (all on the same machine) when I try:

curl --data method=views.get --data view_name="myview" http://mysite/services/json

or